Modified Group Delay Feature for Musical Instrument Recognition

In this work, the modified group delay feature (MODGDF) is proposed for pitched musical instrument recognition. Conventionally, the spectrum-related features used in instrument recognition take into account merely the magnitude information, whereas the phase is often overlooked due to the complications related to its interpretation. However, there is often additional information concealed in the phase, which could be beneficial for recognition. The MODGDF is a method of incorporating phase information, which lacks of the issues related to phase unwrapping. Having shown its applicability for speech-related problems, it is now explored in terms of musical instrument recognition. The evaluation is performed on separate note recordings in various instrument sets, and combined with the conventional mel frequency cepstral coefficients (MFCCs), MODGDF shows the noteworthy absolute accuracy gains of up to 5.1% compared to the baseline MFCCs case.